1. Field of the Invention
The present invention generally relates to a heat sink assembly, and more particularly to a securing device for a heat sink assembly which facilitates the removable attachment of a heat sink module to an electronic device package.
2. The Prior Art
Many high speed and high power electronic devices generate significant amounts of heat which must be dissipated to prevent damage to the device. In some device packages, the heat generated is sufficiently dissipated by the enclosure, header, or leads. For devices which generate high levels of thermal energy, a heat sink having a large surface area is attached to the device to dissipate the generated thermal energy into the surrounding environment thereby preventing overheating thereof. A standard heat sink module has a flat horizontal base with a plurality of vertical cooling elements extending from a top surface thereof, and a bottom surface of the base is in thermal contact with a surface of the device package.
Conventionally, the device package is a microprocessor integrated circuit (IC) received in a pin grid array socket mounted to a printed circuit board. A resilient metal clip is used to clamp the heat sink module to the IC and the socket thereby horizontally mounting the entire assembly to the printed circuit board. The clip is commonly attached by means of special installing tools which complicates the assembly process thereof. Since heat sink modules of different dimension each require a different sized clip for properly engaging with the IC and the socket, each clip must be suitably adapted to facilitate the assembly process which increases manufacturing costs. Such prior art clips for heat sink modules are disclosed in U.S. Pat. Nos. 5,208,731, 5,241,453, 5,276,585, 5,357,404, 5,381,305, and 5,396,402.
As the trend of the computer industry continues toward miniaturization, electronic device packages, such as a CPU, are modularized and vertically mounted onto a PCB by means of a card edge connector for effectively occupying limited space on the PCB. Conventional clips cannot firmly secure a heat sink module to the vertically mounted CPU module. Therefore, the heat sink module may become easily loosened due to affects of shock and vibration acting on the assembly thereby greatly diminishing the heat dissipating capability thereof.
Therefore, an improved securing device for attaching a heat sink module to an electronic device package is required which can overcome the above mentioned drawbacks.